Printing plate trimming mechanism



Aug. 18, 1936. KQHL 2,051,171

PRINTING PLATE TRIMMING MECHANISM Filed Nov. 1, 1933 5 Sheets-Sheet 1 I I I I I I 1 M1 4! I [1 lllll lllllull#ll 3/ INVENTO'R Aug. 18, 1936. 1.. KOHL PRINTING PLATE TRIMMING MECHANISM Filed Nov. 1, 1935 3 Sheets-Sheet 2 INVE N'I'QR i Jd Lc I A'r1 Aug. 18, 1936. KQHL 2,051,171

PRINTING PLATE TRIMMING MECHANISM Filed NOV. 1, 1935 5 Sheets-Sheet 5 Patented Aug. 18, 1936 PRINTING PLATE TRIMMING MECHANISM Leo Kohl, Hollis, N. Y., assignor, by mesne assignments, to R. Hoe & 00., Inc., New York, N. Y., a corporation of New York Application November 1, 1933, Serial No. 696,141'

4 Claims.

This invention in general relates to means for trimming printing plates such as electrotype or stereotype plates, and has for its object the provision of a device particularly designed and adapted to remove the feather edge or burr on the edges of the said printing plates after they are trimmed by a milling cutter.

Another object of the invention is to provide an improved, adjustable burr cutter detachably :mounted on a bevelling or plate trimming machine provided with a milling cutter or its equivalent, the burr cutter being automatically moved from inoperative to operative positions after the plate has been trimmed by the milling cutter.

A further object is to provide a burr cutter assembly of the character indicated with novel means for moving same from inoperative to operative position, and from operative to inoperative position, and for resiliently biasing the burr cutter to either of said positions.

It is also an object of the invention to provide a device of the kind indicated of generally improved construction, whereby the device will be simple, durable and inexpensive in construction, as Well: as convenient, practical, serviceable and efiicient in its use.

The preferred embodiment of the invention is illustrated in the accompanying drawings, where- Figure l is a fragmentary side elevational view of an embodiment of the invention, showing the burr cutter in inoperative position upon a plate trimming machine and the reciprocating table in position to advance'the plate secured thereon to the milling cutter for trimming thereby;

Figure 2 is a fragmentary elevational View, as seen when looking in the direction of the arrow 2 of Figure l; p

' Figure 3 is a fragmentary'elevational view, as seenin the direction of the arrow 3 on Figure2, showing the relation-of the coacting parts when the burr cutting blade has been moved to operative position for removing the burr on the plate during the return or outward travel of the plate carrying table, after the said plate has been trimmed by the milling cutter on the inward movement of the table from the position shown in Figure 1;

Figure 4 is a fragmentary elevational view similar to Figure 3, showing the relation ofthe adjacent coacting parts when the burr cutting blade has been moved to an inoperative positionv prior to the forward movement of the plate conveying table, during which movement the milling cutter trims'the said plate; 3

Figure 5 is a transverse sectional View taken on the line and as viewed in the direction of the arrow 5 of Figure 1, showing the general relation of the coacting parts; and a Figure 6 is a sectional detail view of one of the 5 cutting blades taken on the line and as viewed in the direction of the arrow 3 of Figure 2.

Referring more particularly to the drawings wherein similar characters of reference indicate corresponding parts in the preferred form of the 10 invention, 9 designates the frame of a printing plate trimming and shaving machine provided with milling cutters, indicatedgenerally at l0 which latter, it is to be understood, as illustrated in Figure 1, first operate on a printing plate, while 5 the burr cutters (hereinafter described) are held in inoperative position, the trimming of the plate by the milling cutters ac leaving feather edges or burrs on the two parallel straight edges of the plate ll, the removal of which is accomplished as an immediate subsequent or auxiliary operation by the burr cutters.

On the frame 9 are secured by screws H, apair of supports or brackets !2, having trackways l3, over which travel rollers I4, rotatably secured by bolts or studs l5, to a plate supporting table or carriage IS, the upper arched surface of which is adapted to support a printing plate 11. V

The table I6 which reciprocates over the track-, ways 13 on the rollers I4, is provided with a pair of plate engaging elements or clamps l8, I9 which are adapted to secure the plate ll thereon. The clamp I8 is fixed to the table It, While the clamp l9 has side flanges 2 I, slidably movable in a groove 22 provided in the table, and is threadedly engaged on a screw 23 supported in an outer portion of the table 16. The screw 23 has fastened thereto a hand wheel '24 which is spaced from the adjacent portions of the table by a collar or bracket 25'fastened to the latter. Axial movement of the screw 23 is prevented by a flange 26 formed thereon which is engaged against the bracket 25.

As best shown in Figure 5, the table I6 is provided with a depending web 21, having. a tubular portion or collar 28 receiving threaded bushings or flanged sleeves 29, which are fastened to the said tubular portion by screws 33. The bushings 29 are engaged by a feed spindle or screw 3| rotatably arranged in the table l3 and suitably confined against axial movement therein, the said spindle 3| having a hand operating wheel 32 fastened to an exteriorly protruding end. A collar or sleeve 33 freely rotatable on the spindle 3|, is located between the hub of the hand wheel 32 and 'a bearing 33f The bearing 33 supports the spindle 3| at an adjacent end and is arranged within a journal head or box 34 and confined within the said journal head 34 by a plate or cover 34', which has an opening accommodating the collar 33. Upon the frame 9, a pair of angularly projecting brackets 35, 36 which serve as a supportfor the burr cutters now to be described,

are secured in any suitable'manner as by the In accordance with an important feature of 7 the present invention, a pair; of similar cutting blades or burr cutters 38, 39 are arrangedat the sides of the reciprocating table |6,-the said blades 38, 39 being fastened to holders 40; 4| respectively which are pivotally and adjustably secured, by pivot screws or threaded pins 42 to similar plates or brackets 43, 44, each bracket 43 having g a a slot 45 throughwhich a bolt 46 is passed, the

Figures 3 and 4, each of the blade holders'40,4| 1

have a pair of angularly positioned straight edges 41, 48 which are adapted to be alternately engaged by a spring or resilient member'49, fastened by screws 5| to the adjacent bracket 43 or 44, the said {spring 49 maintaining a follow-up or biasing pressure which serves to retain the adjacent knife holder in operative and inoperative knife hold ing position. Eachr holder 40, 4| has a projection. 52 which is adapted to contact a stop pin 53 in a forwardly inclinedand operativerposition of the said holders as shown in Figure 3, the

bl ades 38, 39 in this position being elevated for effective'trimming of the burr on the plate I1 when thetab le I6 is reciprocated from right, to left. The holders 40, 4| are also'each provided with a pin 54 which is adapted to engage cam surfaces 55,56 formed longitudinally on laterally projecting portions of the adjustable ca plates 51, 58, the'said plates 51, 58 being fas 45" tened in any suitable manner to the table I6, as by the screws which are passedthrough slots 59, 6| provided in the plates 51, 58. The cam surface: 55,'it will be noted, is formed on the I, upper side of the lateral projection arranged on each of the pair of cam plates 51, while the cam' {surface 56is formed on the lower side of the lateral projectionon each of the other pair of cam plates'58. 1 Y V r,

The cams'urfaces 55*and coacting pins 54 when 1 the table l6 has been moved in a direction from left to right to the position illustrated in Figure 1, serve to swing or rock the knife holders 40, 4| into'theinoperative position shown in Figures 1 and 4, while thecam surfaces 56and pins'54 upon the inward travelof the said table H3, in a direction from right to left, coact to swing the knife holders to the position shown in Figure 3 1 where the cutting, blades are elevated sufijciently ,rection, of the blade holders.

to engage 'andfremovel the burr on the straight edges of the printing plate, resulting from the trimming action of the milling cutters iii, the

stop pins 53, mentioned above, serving to anchor I a clockwise di- The slots 59, Bland screws 62- permit the cam plates 51, 58 to be moved axially of the feed spindle or shaft 3|, so that the pins 54 mavengage the camfsu'rfaces 55 at variable positions during the inward and outward reciprocations of I the table IS in order to accommodate platesof Assuming the parts to be hi the position shown in Figure 1, the hand wheel 32 will be turned in a clockwise direction, thereby advancing the table l6, supported by its rollers 14 on the trackway 13, and the printing plate thereon, in a direction from right to left, asviewedin Figure l, and

consequently, bringing the said printing plate l1 into engagement with the milling cutters l0.-

During this movement-from right to left, it will 'be noted that the burr cutters 38, '39 will remain in inoperativev position or out of contact with the two parallel straight edges of the plate H which are being trimmed by the milling cutters I0. After the plate I! has been conveyed inthe same direction to a point where the milling cutters II] have entirely trimmed thestraight edges there- 1 of, further movement in the same direction of "the table IE will bring the cam surface 56 of the cam plate 58 into contact with pin 54 thereby causing the knife holders 40, 4| to be angled into the positionshown' in Figure 3 where the attached blades or burr cutters 38, 39 are inraised operative position. The hand wheel 32 will now be -0 rotated in a reverseor counter clockwise direction, thereby causing the, table Hi to travel in a direction from left to right, thus causing theburr cutters 38, 39 to engage and trim the feather or burr on the two parallel straight edges of the plate I! which have already been trimmed by the still moves in the same direction after the burr cutters have trimmed the feather from the plate,

Imilling cutters; Asjthe reciprocating table II the cam 55 will engagepin 54 on the blade holders 40,4I, and consequently, tilt the latter and their'blades to the inoperative position shown in Figures 1 and 4. The machine in this position 1 is now ready to repeat the cycle; i. e., trim the straight edges of a printing plate and then re- 7 move the burr resulting therefrom, it being observed that a printing plate can be trimmed and the burr thereon removedby a forward and backward reciprocation of the table I5.

It will be understood that the invention may be embodied in other specific forms without'de- 'parting from the spirit or essential attributes thereof, and it is therefore desired that the pres ent embodimentbe considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the invention. 7

' What I claim is: 1

" 1-. In a device of the character described, a

7 table for supporting a plate, means for reciprocating said table, means for adjustably securing the plate to the table, cutting means for operating upon said plate when said table is reciprocated in one direction, a burr cutter effectivefor acting on the plate when the'table is reciprocated in another direction, cam means carried by and reciprocated with said table for moving the burr cutter alternately into operative and inoperative position, and resilient means for biasing the said burr cutter'in either of the said two different positions. Y a a r 2. The combination with a device of the character described having a reciprocating table, means for securing a plate on said reciprocating table, and a milling cutter operating on the'plate;

the scope of of a burr cutter arranged adjacent said table and on a swinging support having a pin, cam means normally fixed to the said table for moving said burr cutter to a position operative for acting upon a plate at a predetermined position of and during one reciprocation of the table and then subsequently moving the burr cutter to an inoperative position at a second reciprocation of the table, and other means for varying the position of the cam means so that the moving of the burr cutter into operative and inoperative positions may take place at different positions of the reciprocating table; said pin coacting with said cam means to move the swinging support and consequently the burr cutter.

3. In a plate beveling machine, a frame, a work table movable forward and backward on the frame, a burr cutter secured to a pivotally supdisposed surface when the table has completed its travel in one direction and thereby move the cutter to inoperative position and to engage the downwardly disposed cam surface when the table has completed its travel in the opposite direction to move the burr cutter to operative position.

4. In a plate beveling machine, a frame, a work table reciprocatingly mounted on the frame, a cutter holder pivotally secured on the frame and adapted to carry a burr cutter and movable to position the cutter in operative and inoperative positions, means for holding the cutter holder in either position, an operating member moving with the work table and having a cam surface arranged on an upper portion of said member and engageable with means on the holder in order to move the cutter into inoperative position at the end of a backward stroke of the table, a second operating member moving with the work table and having a cam surface arranged on a bottom portion of the last mentioned member and engageable with the said means on the holder to move the cutter to operative position at the end of a forward stroke of the table.

LEO KOHL. 

